improve dcm tests to reduce flakiness in endpoints

Addressing a race when patching endpoints resource. This update adds a
polling to ensure the endpoints resource was created. Also, dump all
endpoints and endpointSlice in the test namespace in case of a test
failure, which helps to correlate the current state and what should be
expected in the test scenario.

Example of deployments state log:

```
deployment state: replicas=4 pods=route-scale-in-5b7b4f6b8c-9ncjg/Running/10.128.1.27 // route-scale-in-5b7b4f6b8c-ck45n/Running/10.128.1.28 // route-scale-in-5b7b4f6b8c-srffr/Running/10.128.1.29 // route-scale-in-5b7b4f6b8c-v9hm2/Running/10.128.1.26
```

Example of Endpoints and EndpointSlice resources listed if the test
fails:

```
Endpoints:
NAME                  ADDRESSES                                        NOT READY ADDRESSES  PORTS
route-scale-in        10.128.1.26,10.128.1.27,10.128.1.28,10.128.1.29                       9376
route-scale-in-khbh5  10.128.1.26                                                           9376

EndpointSlices:
NAME                        SERVICE               ADDRESSES                                        NOT READY ADDRESSES  PORTS
route-scale-in-khbh5-8ncmh  route-scale-in-khbh5  10.128.1.26                                                           9376
route-scale-in-rrhzv        route-scale-in        10.128.1.27,10.128.1.28,10.128.1.29,10.128.1.26                       9376
```

https://redhat.atlassian.net/browse/OCPBUGS-85426

Author: jcmoraisjr

test/extended/router/config_manager_ingress.go

@@ -39,6 +39,7 @@ import (
 	exutil "github.com/openshift/origin/test/extended/util"
 )
 
+// execPodRef defines the attributes of the router pod used to execute local HTTP requests
 type execPodRef struct {
 	types.NamespacedName
 	ipAddress string
@@ -47,21 +48,40 @@ type execPodRef struct {
 var _ = g.Describe("[sig-network-edge][Feature:Router][apigroup:route.openshift.io][OCPFeatureGate:IngressControllerDynamicConfigurationManager]", func() {
 	defer g.GinkgoRecover()
 
+	// dcmIngressTimeout defines the maximum amount of time to wait for test operations to complete.
 	const dcmIngressTimeout = 2 * time.Minute
+	// maxDynamicServers defines the number of empty dynamic servers to be allocated when a reload happens.
+	// Some tests use this value as a premise to limit the number of new servers on scale-out operations.
 	const maxDynamicServers = 4
 
 	ctx := context.Background()
 	oc := exutil.NewCLIWithPodSecurityLevel("router-dcm-ingress", api.LevelPrivileged).AsAdmin()
 	kubeClient := oc.AdminKubeClient()
+	routeClient := oc.AdminRouteClient()
 
-	// variables updated on every new test
-	var (
-		execPod          execPodRef
-		controller       types.NamespacedName
-		routeSelectorSet labels.Set
-	)
+	// execPod is the pod used to run requests against the router.
+	var execPod execPodRef
+	// controller is the fully qualified name of the ingress controller resource used in the current test.
+	var controller types.NamespacedName
+	// routeSelectorSet is the label key/value pair that the ingress controller uses to filter route resources.
+	// All route resources should add this label, so the router can find and process them.
+	var routeSelectorSet labels.Set
 
 	g.AfterEach(func() {
+		if g.CurrentSpecReport().Failed() {
+			routes, _ := routeClient.RouteV1().Routes(oc.Namespace()).List(ctx, metav1.ListOptions{})
+			if routes != nil {
+				outputIngress(routes.Items...)
+			}
+			endpoints, _ := kubeClient.CoreV1().Endpoints(oc.Namespace()).List(ctx, metav1.ListOptions{})
+			if endpoints != nil {
+				outputEndpoints(endpoints.Items...)
+			}
+			epsList, _ := kubeClient.DiscoveryV1().EndpointSlices(oc.Namespace()).List(ctx, metav1.ListOptions{})
+			if epsList != nil {
+				outputEndpointSlice(epsList.Items...)
+			}
+		}
 		if controller.Name != "" {
 			err := oc.AdminOperatorClient().OperatorV1().IngressControllers(controller.Namespace).Delete(ctx, controller.Name, *metav1.NewDeleteOptions(1))
 			o.Expect(err).NotTo(o.HaveOccurred())
@@ -73,7 +93,7 @@ var _ = g.Describe("[sig-network-edge][Feature:Router][apigroup:route.openshift.
 		nsOperator := "openshift-ingress-operator"
 		controllerName := names.SimpleNameGenerator.GenerateName("e2e-dcm-")
 
-		// ... and its router is created on router's namespace
+		// ... and its router and service are created in router's namespace
 		nsRouter := "openshift-ingress"
 		svcName := "router-internal-" + controllerName
 
@@ -189,12 +209,12 @@ var _ = g.Describe("[sig-network-edge][Feature:Router][apigroup:route.openshift.
 			// scaling-out to 4 replicas, one at a time
 			for replicas := initReplicas + 1; replicas <= 4; replicas++ {
 
-				g.By(fmt.Sprintf("scaling-out to %d replicas", replicas))
+				framework.Logf("scaling-out to %d replicas", replicas)
 
 				currentServers, err := builder.scaleDeployment(ctx, replicas, dcmIngressTimeout)
 				o.Expect(err).NotTo(o.HaveOccurred())
 
-				g.By("waiting router to add all the backend servers to the load balance")
+				framework.Logf("waiting router to add all the backend servers to the load balance")
 
 				// router should eventually reach all the known replicas
 				eventuallyRouteAllServers(execPod, hostname, false, currentServers, dcmIngressTimeout)
@@ -235,7 +255,7 @@ var _ = g.Describe("[sig-network-edge][Feature:Router][apigroup:route.openshift.
 			// instead of HAProxy removing it from the balance due to health-check starting to fail.
 			for replicas := initReplicas - 1; replicas >= 1; replicas-- {
 
-				g.By(fmt.Sprintf("scaling-in to %d replicas", replicas))
+				framework.Logf("scaling-in to %d replicas", replicas)
 
 				currentServers, err := builder.scaleInEndpoints(ctx, serviceName, replicas)
 				o.Expect(err).NotTo(o.HaveOccurred())
@@ -471,6 +491,7 @@ var _ = g.Describe("[sig-network-edge][Feature:Router][apigroup:route.openshift.
 
 					// ... k8s recreates it and we wait it to be fully functional
 					err = builder.waitDeployment(replicas, dcmIngressTimeout)
+					builder.printDeploymentState(ctx)
 					o.Expect(err).NotTo(o.HaveOccurred())
 				}
 
@@ -637,7 +658,7 @@ var _ = g.Describe("[sig-network-edge][Feature:Router][apigroup:route.openshift.
 			// Iterates over a number of scaling operations, always checking if the change is being applied.
 			for i, replicas := range changingReplicas {
 
-				g.By(fmt.Sprintf("iteration %d, scaling from %d to %d replicas", i+1, prevReplicas, replicas))
+				framework.Logf("iteration %d, scaling from %d to %d replicas", i+1, prevReplicas, replicas)
 
 				currentServers, err := builder.scaleDeployment(ctx, replicas, dcmIngressTimeout)
 				o.Expect(err).NotTo(o.HaveOccurred())
@@ -778,7 +799,12 @@ func (r *routeStackBuilder) createDeploymentStack(ctx context.Context, routetype
 	if err = r.waitDeployment(replicas, timeout); err != nil {
 		return nil, err
 	}
-	return r.exposeDeployment(ctx)
+	backendServers, err = r.exposeDeployment(ctx)
+	if err != nil {
+		return nil, err
+	}
+	r.printDeploymentState(ctx)
+	return backendServers, nil
 }
 
 // scaleDeployment scales-in/out the common deployment to the specified replicas. It waits for all the pods to be created and returns their names.
@@ -796,6 +822,7 @@ func (r *routeStackBuilder) scaleDeployment(ctx context.Context, replicas int, t
 		}
 		return len(backendServers) == replicas, nil
 	})
+	r.printDeploymentState(ctx)
 	return backendServers, err
 }
 
@@ -824,7 +851,14 @@ func (r *routeStackBuilder) createDetachedService(ctx context.Context) (serviceN
 	}
 
 	// we also need the deprecated Endpoints API, since router still uses it depending on the ROUTER_WATCH_ENDPOINTS envvar
-	epCurrent, err := r.kubeClient.CoreV1().Endpoints(svcCurrent.Namespace).Get(ctx, svcCurrent.Name, metav1.GetOptions{})
+	var epCurrent *corev1.Endpoints
+	err = wait.PollUntilContextTimeout(ctx, time.Second, 5*time.Second, false, func(ctx context.Context) (done bool, err error) {
+		epCurrent, err = r.kubeClient.CoreV1().Endpoints(svcCurrent.Namespace).Get(ctx, svcCurrent.Name, metav1.GetOptions{})
+		if err != nil {
+			framework.Logf("error fetching Endpoints: %s", err.Error())
+		}
+		return err == nil, nil
+	})
 	if err != nil {
 		return "", err
 	}
@@ -910,7 +944,7 @@ func (r *routeStackBuilder) scaleInEndpoints(ctx context.Context, detachedServic
 		if err != nil {
 			return err
 		}
-		// deleting addresses, from all subnets, whose IP address is not found in the patched `eps`
+		// deleting addresses, from all subsets, whose IP address is not found in the patched `eps`
 		for i := range ep.Subsets {
 			ss := &ep.Subsets[i]
 			ss.Addresses = slices.DeleteFunc(ss.Addresses, func(addr corev1.EndpointAddress) bool {
@@ -939,6 +973,8 @@ func (r *routeStackBuilder) createServeHostnameDeployment(replicas int) error {
 
 // createDeployment creates the deployment resource. It should be called just once, since it uses the OC namespace and the common resource name.
 func (r *routeStackBuilder) createDeployment(image string, replicas, port int, cmd ...string) error {
+	// This deployment is safe under Single Node OpenShift (SNO): although it can create more replicas,
+	// those replicas does not configure anti-affinity, so all of them can run in the same node.
 	runArgs := []string{"deployment", r.resourceName, "--image", image, "--replicas", strconv.Itoa(replicas), "--port", strconv.Itoa(port), "--"}
 	runArgs = append(runArgs, cmd...)
 	return r.oc.Run("create").Args(runArgs...).Execute()
@@ -953,6 +989,25 @@ func (r *routeStackBuilder) exposeDeployment(ctx context.Context) (backendServer
 	return r.fetchServiceReplicas(ctx)
 }
 
+// printDeploymentState outputs the pod names, status, and their IP addresses. Best effort, it outputs the error instead in case it happens.
+// It requires that `exposeDeployment()` was already called.
+func (r *routeStackBuilder) printDeploymentState(ctx context.Context) {
+	pods, err := r.fetchPods(ctx)
+	if err != nil {
+		framework.Logf("deployment state: error reading deployment pods: %v", err)
+		return
+	}
+	var podDescription []string
+	for _, pod := range pods {
+		var podIPs []string
+		for _, ip := range pod.Status.PodIPs {
+			podIPs = append(podIPs, ip.IP)
+		}
+		podDescription = append(podDescription, fmt.Sprintf("%s/%s/%s", pod.Name, pod.Status.Phase, strings.Join(podIPs, ",")))
+	}
+	framework.Logf("deployment state: replicas=%d pods=%s", len(pods), strings.Join(podDescription, " // "))
+}
+
 // fetchEndpointSlice fetches the EndpointSlice of the provided service name. It currently supports only one EndpointSlice instance for simplicity.
 func (r *routeStackBuilder) fetchEndpointSlice(ctx context.Context, serviceName string) (*discoveryv1.EndpointSlice, error) {
 	listOpts := metav1.ListOptions{LabelSelector: discoveryv1.LabelServiceName + "=" + serviceName}
@@ -967,8 +1022,8 @@ func (r *routeStackBuilder) fetchEndpointSlice(ctx context.Context, serviceName
 	return &epsList.Items[0], nil
 }
 
-// fetchServiceReplicas fetches the pod names from the exposed common deployment. It requires that `exposeDeployment()` was already called.
-func (r *routeStackBuilder) fetchServiceReplicas(ctx context.Context) ([]string, error) {
+// fetchPods fetches the pods from the exposed common deployment. It requires that `exposeDeployment()` was already called.
+func (r *routeStackBuilder) fetchPods(ctx context.Context) ([]corev1.Pod, error) {
 	svc, err := r.kubeClient.CoreV1().Services(r.namespace).Get(ctx, r.resourceName, metav1.GetOptions{})
 	if err != nil {
 		return nil, err
@@ -978,9 +1033,18 @@ func (r *routeStackBuilder) fetchServiceReplicas(ctx context.Context) ([]string,
 	if err != nil {
 		return nil, err
 	}
-	backendServers := make([]string, len(pods.Items))
-	for i := range pods.Items {
-		backendServers[i] = pods.Items[i].Name
+	return pods.Items, nil
+}
+
+// fetchServiceReplicas fetches the pod names from the exposed common deployment. It requires that `exposeDeployment()` was already called.
+func (r *routeStackBuilder) fetchServiceReplicas(ctx context.Context) ([]string, error) {
+	pods, err := r.fetchPods(ctx)
+	if err != nil {
+		return nil, err
+	}
+	backendServers := make([]string, len(pods))
+	for i := range pods {
+		backendServers[i] = pods[i].Name
 	}
 	return backendServers, nil
 }

test/extended/router/stress.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"strconv"
 	"strings"
 	"text/tabwriter"
 	"time"
@@ -16,6 +17,7 @@ import (
 
 	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
+	discoveryv1 "k8s.io/api/discovery/v1"
 	rbacv1 "k8s.io/api/rbac/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -656,6 +658,64 @@ func outputIngress(routes ...routev1.Route) {
 	e2e.Logf("Routes:\n%s", b.String())
 }
 
+func outputEndpoints(endpoints ...corev1.Endpoints) {
+	b := &bytes.Buffer{}
+	w := tabwriter.NewWriter(b, 0, 0, 2, ' ', 0)
+	fmt.Fprintf(w, "NAME\tADDRESSES\tNOT READY ADDRESSES\tPORTS\n")
+	for _, ep := range endpoints {
+		for _, ss := range ep.Subsets {
+			resumeAddrs := func(addrs []corev1.EndpointAddress) string {
+				var addrList []string
+				for _, addr := range addrs {
+					val := "-"
+					if addr.IP != "" {
+						val = addr.IP
+					} else if addr.Hostname != "" {
+						val = addr.Hostname
+					}
+					addrList = append(addrList, val)
+				}
+				return strings.Join(addrList, ",")
+			}
+			var portList []string
+			for _, port := range ss.Ports {
+				portList = append(portList, strconv.Itoa(int(port.Port)))
+			}
+			fmt.Fprintf(w, "%s\t%s\t%s\t%s\n", ep.Name, resumeAddrs(ss.Addresses), resumeAddrs(ss.NotReadyAddresses), strings.Join(portList, ","))
+		}
+	}
+	w.Flush()
+	e2e.Logf("Endpoints:\n%s", b.String())
+}
+
+func outputEndpointSlice(epss ...discoveryv1.EndpointSlice) {
+	b := &bytes.Buffer{}
+	w := tabwriter.NewWriter(b, 0, 0, 2, ' ', 0)
+	fmt.Fprintf(w, "NAME\tSERVICE\tADDRESSES\tNOT READY ADDRESSES\tPORTS\n")
+	for _, eps := range epss {
+		var addrList, notReadyAddrList []string
+		for _, ep := range eps.Endpoints {
+			addrs := strings.Join(ep.Addresses, "+")
+			if ready := ep.Conditions.Ready; ready == nil || *ready == true {
+				addrList = append(addrList, addrs)
+			} else {
+				notReadyAddrList = append(notReadyAddrList, addrs)
+			}
+		}
+		var portList []string
+		for _, port := range eps.Ports {
+			val := "-"
+			if port.Port != nil {
+				val = strconv.Itoa(int(*port.Port))
+			}
+			portList = append(portList, val)
+		}
+		fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\n", eps.Name, eps.Labels[discoveryv1.LabelServiceName], strings.Join(addrList, ","), strings.Join(notReadyAddrList, ","), strings.Join(portList, ","))
+	}
+	w.Flush()
+	e2e.Logf("EndpointSlices:\n%s", b.String())
+}
+
 // findMostRecentConditionTime returns the time of the most recent condition.
 func findMostRecentConditionTime(conditions []routev1.RouteIngressCondition) time.Time {
 	var recent time.Time